The purpose of this research is to examine the longitudinal contributions of father involvement and coparenting relationship quality to children's socioemotional functioning in the 2-parent family context. Levels of father involvement and coparenting relationship quality have both been linked empirically to children's socioemotional functioning (Lamb, 1997; McHale et al., 2002), but prior research on father involvement and coparenting relationships has largely treated these family processes as independent topics of study. Thus, it is understood that parents who frequently support each other's parenting and refrain from undermining each other's parenting efforts foster healthy development in their children (Schoppe, Mangelsdorf, & Frosch, 2001), and that more involved fathering is associated with positive outcomes for children (Parke et al., 2002), but the interplay between these 2 important aspects of family life in relation to children's functioning is less clearly understood. The integration of these 2 lines of research would further the scientific understanding of family processes, and thus, provide clearer recommendations for families and practitioners. Three (3) questions guide this research: 1. What are the concurrent and longitudinal associations between levels of father involvement and coparenting relationship quality? 2. What are the contributions of father involvement and coparenting relationship quality to children's socioemotional functioning over time? 3. How do children's characteristics affect the associations among father involvement, coparenting relationship quality, and children's functioning? The proposed project capitalizes on the Pi's preliminary work initiating the collection of a representative sample of 100 2-parent families with preschool-aged children, who provide self-report and observational data on family processes and child functioning. Funding is sought for the extension of the current data collection effort with a longitudinal component, which would enhance the scientific and practical value of this work.